1. Field of the Invention
The present invention pertains to an inserted rotary cutter having wiper inserts mounted thereon, and more particularly to the improvement in the positioning precision of the wiper inserts.
2. Prior Art
A cutting tool such as an inserted face milling cutter (hereinafter referred to a "face milling cutter") is known, on which a plurality of indexable or throw-away inserts (hereinafter referred to as "inserts") are mounted. In a certain type of this face milling cutter, some wiper or flat drag inserts are included in the normal or usual inserts, to effect a fine or finish processing as well as a coarse processing by a single cutting processing. In such a face milling cutter, the end cutting edges of the wiper inserts project from the end cutting edges of the usual inserts forwardly with respect to the tool body by, for example, 0.06 mm, thereby causing the material surface coarse-processed by the usual inserts to be finished by the wiper inserts.
The tool body of the face milling cutter as described above has a forward end portion whose outer periphery is provided with a plurality of insert mounting seats. The usual and wiper inserts are mounted on the insert mounting seats, and are held and fixed respectively thereto by wedge members and clamp bolts. All of the insert mounting seats are formed with a general manufacturing tolerance.
In the face milling cutter of the kind referred to above, however, positioning of the wiper inserts, which effect the finish processing, requires an extremely high precision as compared with the usual inserts. For this reason, conventionally, with the face milling cutter mounted to a milling machine, a dial gauge or the like is used to measure running-out of the end cutting edges of the wiper inserts to finely adjust the position of the wiper inserts. However, high positioning accuracy cannot be desired by such adjustment. Thus, the wiper inserts are worn prematurely, and the processing accuracy deteriorates. Further, skill and an extended time period are required for the setup of the face milling cutter.
In addition, if each wiper insert has a relatively long end cutting edge, the wiper insert projects considerably from the seat member so that the seating stability of the wiper insert deteriorates. Therefore, so-called chattering vibration tends to occur, resulting in chipping of the cutting edge and skin-roughening of the processed surface.